CNTF and retinal degeneration: Delivery of ciliary neurotrophic factor (CNTF) to patients with advanced retinal degeneration via encapsulated intravitreal implants has been shown to be both safe and effective in phase I clinical trials [4], and is currently under clinical investigation also for geographic atrophy, an advanced form of macular degeneration [43], and achromatopsia (clinical trials.gov).